Issue #8713: Support alternative start methods in multiprocessing on Unix.
See http://hg.python.org/sandbox/sbt#spawn
diff --git a/Modules/_multiprocessing/multiprocessing.c b/Modules/_multiprocessing/multiprocessing.c
index a4c4b2d..30cb5eb 100644
--- a/Modules/_multiprocessing/multiprocessing.c
+++ b/Modules/_multiprocessing/multiprocessing.c
@@ -126,6 +126,7 @@
{"recv", multiprocessing_recv, METH_VARARGS, ""},
{"send", multiprocessing_send, METH_VARARGS, ""},
#endif
+ {"sem_unlink", _PyMp_sem_unlink, METH_VARARGS, ""},
{NULL}
};
diff --git a/Modules/_multiprocessing/multiprocessing.h b/Modules/_multiprocessing/multiprocessing.h
index 68a5984..9aeea8d 100644
--- a/Modules/_multiprocessing/multiprocessing.h
+++ b/Modules/_multiprocessing/multiprocessing.h
@@ -98,5 +98,6 @@
*/
extern PyTypeObject _PyMp_SemLockType;
+extern PyObject *_PyMp_sem_unlink(PyObject *ignore, PyObject *args);
#endif /* MULTIPROCESSING_H */
diff --git a/Modules/_multiprocessing/semaphore.c b/Modules/_multiprocessing/semaphore.c
index dcf3b42..de85a90 100644
--- a/Modules/_multiprocessing/semaphore.c
+++ b/Modules/_multiprocessing/semaphore.c
@@ -18,6 +18,7 @@
int count;
int maxvalue;
int kind;
+ char *name;
} SemLockObject;
#define ISMINE(o) (o->count > 0 && PyThread_get_thread_ident() == o->last_tid)
@@ -397,7 +398,8 @@
*/
static PyObject *
-newsemlockobject(PyTypeObject *type, SEM_HANDLE handle, int kind, int maxvalue)
+newsemlockobject(PyTypeObject *type, SEM_HANDLE handle, int kind, int maxvalue,
+ char *name)
{
SemLockObject *self;
@@ -409,21 +411,22 @@
self->count = 0;
self->last_tid = 0;
self->maxvalue = maxvalue;
+ self->name = name;
return (PyObject*)self;
}
static PyObject *
semlock_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
- char buffer[256];
SEM_HANDLE handle = SEM_FAILED;
- int kind, maxvalue, value;
+ int kind, maxvalue, value, unlink;
PyObject *result;
- static char *kwlist[] = {"kind", "value", "maxvalue", NULL};
- static int counter = 0;
+ char *name, *name_copy = NULL;
+ static char *kwlist[] = {"kind", "value", "maxvalue", "name", "unlink",
+ NULL};
- if (!PyArg_ParseTupleAndKeywords(args, kwds, "iii", kwlist,
- &kind, &value, &maxvalue))
+ if (!PyArg_ParseTupleAndKeywords(args, kwds, "iiisi", kwlist,
+ &kind, &value, &maxvalue, &name, &unlink))
return NULL;
if (kind != RECURSIVE_MUTEX && kind != SEMAPHORE) {
@@ -431,18 +434,23 @@
return NULL;
}
- PyOS_snprintf(buffer, sizeof(buffer), "/mp%ld-%d", (long)getpid(), counter++);
+ if (!unlink) {
+ name_copy = PyMem_Malloc(strlen(name) + 1);
+ if (name_copy == NULL)
+ goto failure;
+ strcpy(name_copy, name);
+ }
SEM_CLEAR_ERROR();
- handle = SEM_CREATE(buffer, value, maxvalue);
+ handle = SEM_CREATE(name, value, maxvalue);
/* On Windows we should fail if GetLastError()==ERROR_ALREADY_EXISTS */
if (handle == SEM_FAILED || SEM_GET_LAST_ERROR() != 0)
goto failure;
- if (SEM_UNLINK(buffer) < 0)
+ if (unlink && SEM_UNLINK(name) < 0)
goto failure;
- result = newsemlockobject(type, handle, kind, maxvalue);
+ result = newsemlockobject(type, handle, kind, maxvalue, name_copy);
if (!result)
goto failure;
@@ -451,6 +459,7 @@
failure:
if (handle != SEM_FAILED)
SEM_CLOSE(handle);
+ PyMem_Free(name_copy);
_PyMp_SetError(NULL, MP_STANDARD_ERROR);
return NULL;
}
@@ -460,12 +469,30 @@
{
SEM_HANDLE handle;
int kind, maxvalue;
+ char *name, *name_copy = NULL;
- if (!PyArg_ParseTuple(args, F_SEM_HANDLE "ii",
- &handle, &kind, &maxvalue))
+ if (!PyArg_ParseTuple(args, F_SEM_HANDLE "iiz",
+ &handle, &kind, &maxvalue, &name))
return NULL;
- return newsemlockobject(type, handle, kind, maxvalue);
+ if (name != NULL) {
+ name_copy = PyMem_Malloc(strlen(name) + 1);
+ if (name_copy == NULL)
+ return PyErr_NoMemory();
+ strcpy(name_copy, name);
+ }
+
+#ifndef MS_WINDOWS
+ if (name != NULL) {
+ handle = sem_open(name, 0);
+ if (handle == SEM_FAILED) {
+ PyMem_Free(name_copy);
+ return PyErr_SetFromErrno(PyExc_OSError);
+ }
+ }
+#endif
+
+ return newsemlockobject(type, handle, kind, maxvalue, name_copy);
}
static void
@@ -473,6 +500,7 @@
{
if (self->handle != SEM_FAILED)
SEM_CLOSE(self->handle);
+ PyMem_Free(self->name);
PyObject_Del(self);
}
@@ -574,6 +602,8 @@
""},
{"maxvalue", T_INT, offsetof(SemLockObject, maxvalue), READONLY,
""},
+ {"name", T_STRING, offsetof(SemLockObject, name), READONLY,
+ ""},
{NULL}
};
@@ -621,3 +651,23 @@
/* tp_alloc */ 0,
/* tp_new */ semlock_new,
};
+
+/*
+ * Function to unlink semaphore names
+ */
+
+PyObject *
+_PyMp_sem_unlink(PyObject *ignore, PyObject *args)
+{
+ char *name;
+
+ if (!PyArg_ParseTuple(args, "s", &name))
+ return NULL;
+
+ if (SEM_UNLINK(name) < 0) {
+ _PyMp_SetError(NULL, MP_STANDARD_ERROR);
+ return NULL;
+ }
+
+ Py_RETURN_NONE;
+}